Tag Archives: interstellar flight

More details about Proxima Centauri’s Earthlike exoplanet

Link here. Lots of background into the discovery itself, but I think these paragraphs really sum things up:

“The search for life starts now,” says Guillem Anglada-Escudé, an astronomer at Queen Mary University of London and leader of the team that made the discovery.

Humanity’s first chance to explore this nearby world may come from the recently announced Breakthrough Starshot initiative, which plans to build fleets of tiny laser-propelled interstellar probes in the coming decades. Travelling at 20% of the speed of light, they would take about 20 years to cover the 1.3 parsecs from Earth to Proxima Centauri.

Proxima’s planet is at least 1.3 times the mass of Earth. The planet orbits its red-dwarf star — much smaller and dimmer than the Sun — every 11.2 days. “If you tried to pick the type of planet you’d most want around the type of star you’d most want, it would be this,” says David Kipping, an astronomer at Columbia University in New York City. “It’s thrilling.”

The human race now has a real interstellar target to aim for. Don’t be surprised if we get there sooner than anyone predicts.

Using lasers to travel to the stars

The competition really heats up! A research team at the University of California, Santa Barbara (UCSB) has proposed that an array of space-based lasers can be used to accelerate a solar sail to speeds as much as 26% the speed of light, thus making interstellar travel possible.

[The] key breakthrough was the development of modular arrays of synchronized high-power lasers, fed by a common “seed laser.” The modularity removes the need for building powerful lasers as a single device, splitting them instead into manageable parts and powering the seed laser with relatively little energy. Lockheed Martin has recently exploited this advance to manufacture powerful new weapons for the US Army. In March last year, the aerospace and defense giant demonstrated a 30 kW laser weapon (and its devastating effect on a truck). By October, the laser’s power had already doubled to 60 kW and offered the option to reach 120 kW by linking two modules using off-the-shelf components.

The UCSB researchers refer to their own planned arrays as DE-STAR (Directed Energy System for Targeting of Asteroids and ExploRation), with a trailing number to denote their size. A DE-STAR-1 would be a square array 10 meters (33 ft) per side and about as powerful as Lockheed’s latest; at the other end of the spectrum, a DE-STAR-4 would be a 70 GW array covering a massive area of 100 square kilometers (39 square miles).

…Lubin stresses that even a relatively modest orbital array could offer interesting propulsion capabilities to CubeSats and nanosatellites headed beyond Earth orbit, and that useful initial tests would still be conducted on the ground first on one-meter (3-ft) arrays, gradually ramping up toward assembling small arrays in orbit. While even a small laser array could accelerate probes of all sizes, the larger 70-GW system would of course be the most powerful, capable of generating enough thrust to send a CubeSat probe to Mars in eight hours – or a much larger 10,000-kg (22,000-lb) craft to the same destination in a single month, down from a typical six to eight.

Further upgrades would make it possible to send a cubesate and its lightsail to Alpha Centuri in about fifteen years.

The important point here is that it appears that all the technology for building this already exists, or is relatively straightforward to develop.